Lazuline Sabre-wing (Campyloterus lazulus), John Gould It will be seen that I have followed preceding ornithologists in considering the Trochilus lazulus of Vieillot’s “Galerie des Oiseaux,” and the T. fadcatus of Swainson’s “Zoological Illustrations,” as identical; at the same time I must remark, that neither of their figures nor the accompanying descriptions are quite correct; Vieillot figuring and describing the under tail-coverts as white, and Swainson as green, whereas these feathers are really deep chestnut; with this exception the two figures agree with the bird here represented. This illustration has been restored to its original vibrancy by enhancing colors and removing unwanted marks. A monograph of the Trochilidæ, or family of humming-birds was published between 1849 and 1887 by English ornithologist John Gould. This monumental work depicts and describes all the known species of hummingbirds at the time - comprising 418 lithographic plates and information on 537 species."